Scary reality of turbulence revealed after horror Singapore Airlines flight leaves one dead, many injured

There is a reason why pilots on the horror Singapore Airlines flight likely didn’t see the “sudden extreme turbulence” coming.

One person is dead and dozens have been injured after a Singapore Airlines flight hit “sudden extreme turbulence” – leaving many travellers wondering how it could have possibly happened.

Meal service was underway when flight SQ321 from London to Singapore – with 211 passengers, including 56 Australians, and 18 crew on board – suffered a sudden drop.

“If the pilot had thought there was a problem, he or she would have suspended meal service,” Emeritus Professor Jason Middleton, who was head of the UNSW School Of Aviation from 1995 to 2017, told news.com.au.

Flight SQ321 from London to Singapore experienced “sudden extreme turbulence”. Picture: X

Blood splatters could be seen in pictures of the plane. Picture: X

He said the reality was that aircraft do not have a turbulence monitor, and it is why he only ever takes his seat belt off to go the aircraft lavatory.

“The [weather] radar doesn’t show turbulence, the radar only shows rainfall, it only shows water droplets,” he said.

Prof Middleton explained that when pilots see patches of heavy rain and thunderstorms showing up on the radar, they will avoid it, however, areas showing up clear on the radar do not necessarily have no clouds or turbulence there – there are just no water droplets big enough to be detected.

This could be one of two possible explanations as to why the extreme turbulence on flight SQ321 felt as if it came out of nowhere.

Unexpected turbulence in clouds

Prof Middleton said one possible cause of the unexpected turbulence may have been clouds without rain.

“If they’re already within the clouds somewhere … they can’t see visually [out the cockpit window] because they’re in clouds,” he said. “You’d be lucky to see a few hundred metres or a kilometre in cloud.

“You can’t see what’s coming ahead, the weather radar is showing there is no precipitation, there’s no way known that the pilot can actually figure out ... he or she might suspect there’s turbulence because they’re already getting some but they don’t know exactly where it is and can’t avoid it.”

The sudden turbulence could also have been hit in clear skies with no clouds.

Ambulances took injured passengers from the plane to hospital after an emergency landing at Suvarnabhumi International Airport in Thailand. Picture: EPA/Rungroj Yongrit

Clear air turbulence

Clear air turbulence can be caused by jet streams, narrow bands of strong wind in the upper levels of the atmosphere.

“Those winds can be 120-150km/h,” Em Prof Middleton said. “If you’ve got very strong winds and slower air below, then what you’ll have is a turbulent layer between the strong winds and the weak winds.”

He said that happens in “absolutely clear air” where there may not even be a trace of water vapour.

Todd Lane, an atmospheric science professor at Melbourne University, told news.com.au while it was well known thunderstorms are source of turbulence, the air around thunderstorms that is not cloudy can have a lot of turbulence as well.

“What we know from our research on this is that thunderstorms can generate turbulence from up to 100km away from the storm,” Prof Lane said.

“So you can be quite a significant distance away from a thunderstorm but it still generates some turbulence and this is often a cause of these types of unexpected encounters where the aircraft is a long way away from a thunderstorm, the air is smooth, the seatbelt sign is not on and then you might hit a small patch of unexpected turbulence.”

He added that 97 per cent of injuries associated with turbulence was from people not wearing their seat belt, although he assured big turbulence events like on the Singapore Airlines flight are “quite rare”.

“It has to be a significant vertical deviation of the aircraft or big turbulence event for people to get injured like this,” he said.

“What we more commonly experience is the smaller choppy turbulence where you’re not going to fly out of your seat, it’s just uncomfortable.”

Intertropical Convergence Zone

The experts said that the area in which the plane was flying is called the Intertropical Convergence Zone, an area near the equator where turbulence is common.

“It’s a known area of thunderstorms and because thunderstorms are very common there, turbulence is also more likely,” Prof Lane said.

Em Prof Middleton explained: “The warmest oceans in the world occur around Asia and so the heat transfer into the atmosphere from the surface of the ocean is larger in Asia than it is everywhere else.

“Hot air rises and so that’s why you get cloud towers in the tropics with the hot moist air rising.”

He said high clouds can happen at any time of day in the area.

“The cloud tops are over 40,000 feet in that area, typically, and can be even at night,” he said.

The aftermath of flight SQ321

About 10 hours after Singapore Airlines flight SQ321 departed London’s Heathrow Airport, it encountered “sudden severe turbulence” over the Irrawaddy Basin in Myanmar at an altitude of 37,000 feet.

The pilot declared a medical emergency and diverted the Boeing 777-300ER to Bangkok.

One passenger, 73-year-old grandad Geoff Kitchen, died, while others were taken to hospital.

British man Geoff Kitchen, 73, died on the flight.

A relief flight took 143 of the passengers and crew members, who were able to travel, to Singapore.

The airline said another 79 passengers and six crew members remained in Bangkok, which included those receiving medical care, as well as their family members and loved ones who were on the flight.

Singapore Airlines said it was fully co-operating with authorities investigating the incident.

“On behalf of Singapore Airlines, I would like to express my deepest condolences to the family and loved ones of the deceased passenger,” Singapore Airlines CEO Goh Choon Phong said.

“We also deeply apologise for the trauma experienced by all passengers and crew members on this flight. We are providing all possible assistance and support to them, along with their families and loved ones, during this difficult time.

“The wellbeing of our passengers and staff is our utmost priority.”